81742B Hayes Energize III Plus - Proportional

Replaces 81741B and 81745

Install your Hayes electric trailer brake controller quickly and easily with this custom wiring adapter. One end plugs into the controller, and the other plugs into the junction box beneath your vehicle's dash.

Custom connector end plugs into the electric junction box beneath the dash of your vehicle

Opposite end plugs into the back of your electric brake controller

Compatible with time-delayed and proportional brake controllers from Hayes

Made in the USA

Installation of Hayes Brake Controller Adapter

To install your Hayes electric brake controller, you need to connect the wiring of the controller to your vehicle. Certain auto manufacturers offer pre-wired options, typically known as tow packages, in which the wiring is run for you from the dash to the trailer connector on the back of your vehicle. Usually when this is done, a port is installed at your dash so that you can easily plug in a brake controller.

This adapter plugs into the port that is built into the electric junction box underneath your vehicle's dash. The black box is located to the left of the steering column, just above the carpet. To plug in the adapter, first remove the cover on the box. The adapter plugs into the second slot from the left, on the top row.

No hardwiring is required to install this adapter. After you plug it into the factory port, you simply plug the other end of the adapter directly into your electric trailer brake controller. Because there are no wires to connect, installation is not permanent. You can unplug and remove your brake controller at any time to transfer it to another vehicle or securely stow it away.

Today we are going to be taking a look at the Hayes Enegerize III Plus. This is an electric brake controller. This proportional brake controller is for use on all trailers with 2, 4, or 6 electric trailer brakes. A proportional brake controller works in direct proportion to the tow vehicles braking effort, so basically the more deceleration detected by the internal censor, the greater the amount of power that is delivered to the trailer brakes. This offers faster and smoother stopping performance, as well as extra power and control. It activates immediately, so there is no pausing like when using time delay brake controllers.

It's going to provide automatic and manual trailer braking with 100% braking power in manual mode. This brake controller features built in safe guards that are designed to protect your vehicle and your trailer. Some of those safe guards, I'm going to mention 3 of them. The first one is that the trailer and tow vehicle stop lights will operate when the trailer brakes are applied automatically or manually with the brake controller. The unit has built in short circuit protection from trailer brake wiring and it's going to feature hazard flash immunity that prevents pulsing of the brakes when the flashers are activated on the tow vehicle when the controller is adjusted correctly. Now the unit is going to come with detailed installation instructions. They are going to help with the initial setup.

It's going to go through owner responsibilities and it's going to walk you through the entire process of getting the unit out of the packaging to fully installed in your particular vehicle. Now right here on the front of the controller, there is going to be a red LED indicator. This will illuminate from dim to bright when stopping and will return to dim when deceleration is no longer detected. When the tow vehicle brake pedal is released, the controller and the red indicator will be turned off. The units also going to feature a gain wheel, that's located right here, that allows you to increase or decrease the amount of power being sent to your trailer brakes. On this side of the unit, it's going to have a deceleration sensor lever, that's going to let you adjust the braking aggressiveness. Then right here also at the front, it's going to have the slide bar manual override, so the further the lever is moved, the greater the amount of braking power that's applied manually to the trailer brakes.

This operation is an independent circuit and overrides the gain wheel adjustment, to allow full braking effort whenever needed. The unit is going to come with your mounting bracket, as well as your installation hardware. It's also going to come with VHB tape, which stands for very high bonding. This tape is included for an easier installation. You just peel that off, stick it to the unit and then stick it to the mounting surface. It's also going to come with a cleaning pad, so that way you can effectively clean the mounting surface when you're mounting it with the VHB tape. It's going to come with the 2 installation options.

Hardware is included. Everything that you need to get it installed is included. The controller is a really nice design, pretty compact. We'll take some measurements here in a couple of minutes, but it does come with the installation bracket. On the sides you're going to have 4 anchor holes, or adjustment holes, so you can choose whatever one works best for your application. Now when it comes to mounting, it does offer a wide range of mounting positions and pendulum adjust ability. Mounting angles between -35 and +90 degrees can be accommodated by this controller. Please keep in mind that the unit must be installed so that it is parallel with the travel of the tow vehicle and the trailer. When it comes to the wiring, the units going to feature the Hayes quick connect wiring, that makes connecting and disconnecting the brake controller quick and easy. The wiring simply plugs into a vehicle specific wiring adapter. Now those adapters are sold separately, they are available at etrailer.com, so you can check out that option to see if a wiring adapter is available for your vehicle. If you don't want to use that wiring adapter, you can cut that off, expose the wires and you can use it as a hard wire application as well. A few measurement to go over with you real quick starting with the overall width of the unit. Edge to edge, we're looking at a measurement of about 3 1/4 inches wide. Taking a look at the length from back to front, that is going to give us a length measurement of about 5 3/8 of an inch. Then when it comes to the thickness, that's going to give us a thickness of about 1 3/8 of an inch. The product is also made right here in the U.S.A. That's going to do it for today's look at the Hayes Energized III Plus.

Order: Install your Hayes electric trailer brake controller quickly and easily with this custom wiring adapter. One end plugs into the controller, and the other plugs into the junction box beneath your vehicle's dash.

- HA81742B

by: Amanda07/31/2019

Easy to assemble and etrailer made sure that I had everything I needed to install the brake control system. Order arrived on time and will definitely order from etrailer again.
678721

- HA81781-HBC

by: Eric H.06/02/2015

Along with wiring harness ordered a Hayes controller and a trailer jack. Was hoping for a Friday delivery. Items were setting on front porch midday Thursday! Once again outstanding service and products.
199809

- HA81742B

by: James08/04/2018

Very pleased with the Hayes controller and the installation videos and information available at etrailer. My installation was hardwired due to an earlier install which removed a connector, so etrailer support was very beneficial plus their price was very competitive...a winning combination.
549748

- HA81781-HBC

by: William06/29/2019

2001 Chevrolet Silverado

I was needing to install a brake controller in a newly-acquired 2001 GM pickup. The truck already had an available plug-in port, and I was looking for a connection cable between it and the controller. Due to their strong reputation for good business, I checked with eTrailer first. They not only had exactly what I needed, but the price was about the lowest around. I ordered the cable, and the shipping was fast. As expected, the cable fit perfectly, and was the precise length necessary. I have used this company before this order, and rest assured, I will do it again.
664464

- HA81742B

by: Ken05/31/2019

my second one in another truck, works well for my heavy race trailer
650873

The brake controller you sent in a picture of will only affect the brakes of a trailer you would be towing. It does not affect the brakes of your vehicle in any way if you were to leave the controller installed.
I attached an FAQ article on brake controllers for you to check out as well.view full answer...

All you need for the red wire of your brake controller is a circuit that sees voltage only when the brakes are applied. If you wanted to run a wire to the fuse box to find a wire like you said that would work fine. Some people will also use the third brake light circuit as well.
It almost sounds like you are running the blue wire of the controller to the stop light circuit if the brakes lock up when you tap them. Or your brake controller is just set too aggressively.
I attached aview full answer...

Yes, the signal for the trailer brakes comes from the stop light lead. The red wire on the controller is meant to be connected to the stop light circuit which is the light blue or orange wire on GM vehicles with the factory tow package. This wire will then send a signal to the brake controller when the brake pedal is pressed which in turn sends power to the trailer.
I would first start off by testing the light blue stop light wire on your 2009 Chevrolet Silverado. You will want to useview full answer...

For your 2001 Dodge Ram 1500 the Hayes Energize III part # HA81742B that you referenced can be installed if you use the install harness part # HA81782-HBC that you referenced as that is the custom fit harness designed for your truck.view full answer...

I am not sure which Hayes brake controller that you have, but in reviewing the installation instructions for the Hayes-Lemmerz Energize III+ Electric Trailer Brake Controller # HA81742B I found that there is a section that goes over if the "Controller red indicator on all the time."
The solutions they offer call for testing the Red wire and the Blue wire on the brake controller with a circuit tester like part # PTW2992. The Red wire connects to your Stop Light Switch and only receivesview full answer...

You will need to start with a 4-way (if you do not have one) installed on your 2012 Volvo XC60 to install a brake controller. For that you would want the # 118739 which I attached an install video for.
From there you would need to convert the 4-way to a 7-way so that you can install the Hayes brake controller # HA81742B. For that you will want the Brake Controller Install Kit and 7-Way Adapter part # ETBC7. I attached installation instructions and an install video for this product asview full answer...

The Hayes Energize III brake controller part # HA81742B that you referenced will work great on a tandem axle trailer that has one brake axle. That means your trailer has two assemblies which is perfect with this controller.view full answer...

Info for these parts were:

Edited by:

Lindsey S

Updated by:

Laura H

Updated by:

Sarah W

Installed by:

Cole B

Written by:

Tammy D

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